I've just read this page: http://en.wikipedia.org/wiki/Tag_question
So regarding this passage:
The term "question tag" is generally preferred by British grammarians, while their American counterparts prefer "tag question".
If a British person uses the term "question tag", does it refer to the American term "tag question"? Is this passage saying the terms are synonymous?
As far as I can tell, "tag question" is a term referring to the "question" and "question tag" is a term referring to the "tag" itself, which means they refer to different things and are NOT synonymous. So why does Wikipedia say that the term "question tag" is generally preferred by British grammarians, while their American counterparts prefer "tag question" when they in fact refer to different things (which means that both British and American will have to use either depending on which term they are talking about)?
"Here's a question tag" means "Here's a tag, and the tag is the question tag".
"Here's a tag question" means "Here's a question, and the question is a tag question."
So are "tag" and "question" synonymous? If not I can't see how "tag question" and "question tag" are synonymous.